******* amiga.lib/CheckRexxMsg ************************************************
*
*   NAME
*	CheckRexxMsg - Check if a RexxMsg is from ARexx
*
*   SYNOPSIS
*	result = CheckRexxMsg(message)
*	D0                    A0
*
*	BOOL CheckRexxMsg(struct RexxMsg *);
*
*   FUNCTION
*	This function checks to make sure that the message is from ARexx
*	directly.  It is required when using the Rexx Variable Interface
*	routines (RVI) that the message be from ARexx.
*
*	While this function is new in the V37 amiga.lib, it is safe to
*	call it in all versions of the operating system.  It is also
*	PURE code, thus usable in resident/pure executables.
*
*   NOTE
*	This is a stub in amiga.lib.  It is only available via amiga.lib.
*	The stub has two labels.  One, _CheckRexxMsg, takes the arguments
*	from the stack.  The other, CheckRexxMsg, takes the arguments in
*	registers.
*
*   EXAMPLE
*	if (CheckRexxMsg(rxmsg))
*	{
*		/* Message is one from ARexx */
*	}
*
*   INPUTS
*	message		A pointer to the RexxMsg in question
*
*   RESULTS
*	result		A boolean - TRUE if message is from ARexx.
*
*   SEE ALSO
*	GetRexxVar(), SetRexxVar()
*
*******************************************************************************

******* amiga.lib/GetRexxVar **************************************************
*
*   NAME
*	GetRexxVar - Gets the value of a variable from a running ARexx program
*
*   SYNOPSIS
*	error = GetRexxVar(message,varname,bufpointer)
*	D0,A1              A0      A1      (C-only)
*
*	LONG GetRexxVar(struct RexxMsg *,char *,char **);
*
*   FUNCTION
*	This function will attempt to extract the value of the symbol
*	varname from the ARexx script that sent the message.  When called
*	from C, a pointer to the extracted value will be placed in the
*	pointer pointed to by bufpointer.  (*bufpointer will be the pointer
*	to the value)
*
*	When called from assembly, the pointer will be returned in A1.
*
*	The value string returned *MUST* *NOT* be modified.
*
*	While this function is new in the V37 amiga.lib, it is safe to
*	call it in all versions of the operating system.  It is also
*	PURE code, thus usable in resident/pure executables.
*
*   NOTE
*	This is a stub in amiga.lib.  It is only available via amiga.lib.
*	The stub has two labels.  One, _GetRexxVar, takes the arguments
*	from the stack.  The other, GetRexxVar, takes the arguments in
*	registers.
*
*	This routine does a CheckRexxMsg() on the message.
*
*   EXAMPLE
*
*	char	*value;
*
*	/* Message is one from ARexx */
*	if (!GetRexxVar(rxmsg,"TheVar",&value))
*	{
*		/* The value was gotten and now is pointed to by value */
*		printf("Value of TheVar is %s\n",value);
*	}
*
*   INPUTS
*	message		A message gotten from an ARexx script
*	varname		The name of the variable to extract
*	bufpointer	(For C only) A pointer to a string pointer.
*
*   RESULTS
*	error		0 for success, otherwise an error code.
*			(Other codes may exists, these are documented)
*			3  == Insufficient Storage
*			9  == String too long
*			10 == invalid message
*
*	A1		(Assembly only)  Pointer to the string.
*
*   SEE ALSO
*	SetRexxVar(), CheckRexxMsg()
*
*******************************************************************************

******* amiga.lib/SetRexxVar **************************************************
*
*   NAME
*	SetRexxVar - Sets the value of a variable of a running ARexx program
*
*   SYNOPSIS
*	error = SetRexxVar(message,varname,value,length)
*	D0                 A0      A1      D0    D1
*
*	LONG SetRexxVar(struct RexxMsg *,char *,char *,ULONG);
*
*   FUNCTION
*	This function will attempt to the the value of the symbol
*	varname in the ARexx script that sent the message.
*
*	While this function is new in the V37 amiga.lib, it is safe to
*	call it in all versions of the operating system.  It is also
*	PURE code, thus usable in resident/pure executables.
*
*   NOTE
*	This is a stub in amiga.lib.  It is only available via amiga.lib.
*	The stub has two labels.  One, _SetRexxVar, takes the arguments
*	from the stack.  The other, SetRexxVar, takes the arguments in
*	registers.
*
*	This routine does a CheckRexxMsg() on the message.
*
*   EXAMPLE
*
*	char	*value;
*
*	/* Message is one from ARexx */
*	if (!SetRexxVar(rxmsg,"TheVar","25 Dollars",10))
*	{
*		/* The value of TheVar will now be "25 Dollars" */
*	}
*
*   INPUTS
*	message		A message gotten from an ARexx script
*	varname		The name of the variable to set
*	value		A string that will be the new value of the variable
*	length		The length of the value string
*
*
*   RESULTS
*	error		0 for success, otherwise an error code.
*			(Other codes may exists, these are documented)
*			3  == Insufficient Storage
*			9  == String too long
*			10 == invalid message
*
*   SEE ALSO
*	SetRexxVar(), CheckRexxMsg()
*
*******************************************************************************